由加拿大科學(xué)家凱西·休伯特率領(lǐng)的一個國際研究小組，在挪威附近的北冰洋下低于攝氏零度的沉積物中,，發(fā)現(xiàn)了一種數(shù)目不菲,、處于冬眠狀態(tài)的嗜熱菌。這種細(xì)菌以細(xì)菌芽孢狀態(tài)存在,，在低于零攝氏度的海底冬眠,。該項發(fā)現(xiàn)有可能使科學(xué)家有機(jī)會追蹤到來自海底以下的熱環(huán)境中滲出的熱流，從而可能利用這種手段找到海底蘊(yùn)藏的石油和天然氣,。相關(guān)研究報告發(fā)表在9月18日出版的《科學(xué)》雜志上,。
研究小組發(fā)現(xiàn)，這種嗜熱菌以孢子形式冬眠于北冰洋海底的沉積物中,，這樣可以抵御其所處的惡劣環(huán)境條件,。他們進(jìn)行的實驗顯示，在攝氏40度到攝氏60度之間,，這些孢子就可以復(fù)活為細(xì)菌,。因此科學(xué)家認(rèn)為，這些冬眠細(xì)菌可能來自于大洋底部之下的某些熱區(qū)域,。
領(lǐng)導(dǎo)該項研究工作的休伯特博士目前接受加拿大自然科學(xué)和工程研究委員會的資助,，在德國與多國科學(xué)家開展合作研究。他表示,，最令他們關(guān)注的是,，這種細(xì)菌與取自海底石油的細(xì)菌在遺傳特征上有許多相似性。目前他們正在調(diào)查研究這些細(xì)菌究竟來自何處,，如果這些細(xì)菌來自于某個泄漏的海底石油儲藏地,，那么這種細(xì)菌在今后的利用價值就顯而易見了。
由于這些細(xì)菌屬厭氧菌,，而且其在海底沉積物中存量可觀,，源源不斷，這顯示它們來自于一個巨大的無氧生活環(huán)境,。休伯特教授認(rèn)為,，一種可能是它們來自于大洋深處的高壓原油儲藏區(qū)域，向上泄漏的原油將其帶入了海底水域,。另一種可能是海底“黑煙囪”或其他熱流口的存在,，產(chǎn)生的熱液流動將其帶出。但這種嗜熱菌究竟來自何處,，還需要進(jìn)一步研究實驗確證,。（生物谷Bioon.com）
生物谷推薦原始出處：
Science 18 September 2009:DOI: 10.1126/science.1174012
A Constant Flux of Diverse Thermophilic Bacteria into the Cold Arctic Seabed
Casey Hubert,1,* Alexander Loy,2 Maren Nickel,1 Carol Arnosti,3 Christian Baranyi,2 Volker Brüchert,1,Timothy Ferdelman,1 Kai Finster,4 Flemming M?nsted Christensen,4,5 Júlia Rosa de Rezende,1,5 Verona Vandieken,1, Bo Barker J?rgensen1,5
Microorganisms have been repeatedly discovered in environments that do not support their metabolic activity. Identifying and quantifying these misplaced organisms can reveal dispersal mechanisms that shape natural microbial diversity. Using endospore germination experiments, we estimated a stable supply of thermophilic bacteria into permanently cold Arctic marine sediment at a rate exceeding 108 spores per square meter per year. These metabolically and phylogenetically diverse Firmicutes show no detectable activity at cold in situ temperatures but rapidly mineralize organic matter by hydrolysis, fermentation, and sulfate reduction upon induction at 50°C. The closest relatives to these bacteria come from warm subsurface petroleum reservoir and ocean crust ecosystems, suggesting that seabed fluid flow from these environments is delivering thermophiles to the cold ocean. These transport pathways may broadly influence microbial community composition in the marine environment.
1 Biogeochemistry Group, Max Planck Institute for Marine Microbiology, Celsiusstrasse 1, D-28359 Bremen, Germany.
2 Department of Microbial Ecology, University of Vienna, Althanstrasse 14, A-1090 Vienna, Austria.
3 Department of Marine Sciences, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599–3300, USA.
4 Department of Biological Sciences–Microbiology Section, Aarhus University, Ny Munkegade, Building 1540, DK-8000 Aarhus C, Denmark.
5 Center for Geomicrobiology, Department of Biological Sciences, Aarhus University, Ny Munkegade, Building 1535, DK-8000 Aarhus C, Denmark.
